Rotary drier



June 2, 1931. G. BECHTEL- 1,808,626

I ROTARY DRIER I I Filed May 15, 1929 s Sheets-Sheet INVENTOR ATTORNEY June 2, 1931. e. M. BEC-HTEL ROTARY DRIER 7 Filed May 15, 1929 Sheets-Sheet 2 INVENTOR ZecAzeL WlTNESS ATTORNEY June 2, 1-931. G. M. BECHTEL ROTARY DRIER Filed May 15, 1929 3 Sheets-Sheet I 3 WITNESS W141? ATTORN EY Patented June 2, 1931 1 stars .GERHARD mortars BEcH'rn or ALLnn'rowN, PEivNsjzLviinIA ROTARY DRIER Application filed May is; 1929. serial No. 362,683. Q

' This invention relates to driers of the revolving drum type in which the material" to be treated is fed into one end of an in clined rotating cylinder or drum and dis 5 charged from the other end, and-in its travel the material being treated is subjected to a current of hot air passing in a direction opposite to that in which the material is traveling. r

In driers of this type the elongated cy-- lindrical shell revolves'about its longitudinal axis in one continuous rotating motion and the direction may be either clockwise or counter clock wise. The feed end of the drier is slightly raised to a higher elevation than the discharge end and during the rota-' tion thereofthe material travels from the high towards the low end. Through this cylinder from the lower towards the upper end is directed a current of heated air which travels with a velocity equal to thedraft produced by the stack or exhaust fan located at the other end of the cylinder; During this operation a very'small portion onlyof the material to be dried contacts the heated gases, the greater portion of the gases pass ing through the drier shell without contacting the material to be dried.

A primary ob 'ect of thisinvention is to overcome these objectional features and provide means whereby the heated air or gases are checked in their flow through the drier shell and brought into direct contact with the material to be treated causing a thor-' ough commingling of the gases or heated air with the material to be dried. I v

Another object of the invention is toprovide an apparatus whereby the heated gases 40 being dried for a maximum length of time thereby producing a complete andthorough drying of the material with a minimum con.-

sumption of fuel. a

Another object of the inventionis-to provide a drying cylinder with means whereby the heated air or gases is caused to passin a zig-zag path through the cylinder whereby the gases are contacted with the. material a number of times and for longerperiods;

are held in direct contact with the material .thereby insuring the complete drying of the material with high efficiency. a

Another object ofthe invention is to so construct a drying shell that the battle plates for the gases perform the double function's- 1 of agitators for the material whereby it is commingled and thoroughly exposed to the dryingactionof a heated air current In carrying out these objects, the-invention is susceptible of;a wide range of modification without departing from. the spirit or sacrificing any of the advantages of the claimed invention; there being shown in the drawings for illustrative purposes a preferred and practical form in which; 1

Figure 1 representsa top plan view-"of a rotary drier constructed in accordance with this invention shown in connection with the furnace for supplying heat thereto and a POI-tion of the storage bins in which the-ma- :e 'terial tobe-treated is located;"

Fig. is a longitudinal section thereof with the feed hopper and exhaust hood shown in side'elevation; v r

Fig. 3- is a transverse section of the drier I r cylinder taken on the line3'3 of'Fig. 2;

Fig. 4 is a similar view taken on the-line 4-40f Fig. 2; 1

Fig. 5 is atransverse section through the drier drum or cylindershowing on an em 8 2 larged scale one of thecombined battles and" agitators constituting a partyof this invention;- I

Fig. 6 is a similar'lview taken throughthe furnace; 1

Fig. 7 is an enlarged detail longitudinal -section showing of thef deflectors or baflies in side elevation; and a Fig. .8- is a detail perspective view. ofifone of the agitator blades forming :a partof'the bafile; A i

- Fig. 9 is an enlargeddetail section ofthe self-adjusting connection taken on the "line f 99 of Fig.5. I I In the embodiment illustrated an'ordi-nary, furnace'is'used such as is employed in apparatus of thischaracter and .which-isahere indicated by. the numeral 1f. Thisfurnace 1 has a pit 2 located at one end thereof which is designed'to receive, theljdried material 9- an I I after it has passed/through the drying cyl- 1 inder or drum 107which discharges at its lower end thereinto,- said cylinder being open at this end to permit the free passage of the heat currents from the furnace through the cylinder.

This drum or cylinder'l O may be mounted and rotated,- in; any suitable ,l naznner well 'known to those familiar with. this art it being here shown'in the formof a large hollow cylinder preferably constructed of steel plates securely riveted together along their longitudinal and circumferential'seams and is of a diameter and length to suit the. capacity required." This cylinder 10 is surrounded by two bearing rings llwa'nd lQ known in the art as steelft ires which are mount d so as to rideon suitable sapports cons'tructed soas t-orender the-rotation of the cylinder as free and frictionless as possi-ble. The {supports .13 and' 14 here shown are provided with. the necessary bearing shafts and rollers on which thewtires ride while the, drier is being rotated, the upper or rear end support ,being considerably higher than the frontsupport sons to insure t-he-pro13er in:- cli'nation of the cylinder. 'Ihese supports 1-3 "and ;14 .may bemounted on any suitable foundation, concrete blocks or pillows 1-5 and 16 being here shown forth-is purpose. A ring gear 17 also surroundsthe drum 10 and meshes. witha drive pinion 18 carried on-a-counter "shaft 19' which *inJ-tH-rn is dri ven'by .IDGELDS of a 'belt pulley 20' which ishere shown d'riven-by a motorj2-l-sl I The higher. rear; end of the drunr ELEO is also open has, opening -tlhe-reinto afeed pipe 22 which leads from a feed-hopper '23. This feed pipe controls the-flow-o'f 'lI lttelllt l.

from the'bin or hopper-to the drier by means of a" suitable :gate not shown and which is so setito cause the flow :o'f'materi'al tothe drier to be uniform. An exhaust fhood; 24

engages the drier cylinder 10 its'hi g'rh 7 end andmaybe connected to an exhaust fan orto a stack. This exhaust hood 24 is provided with an fopeni-ng in :thegtop to con nect to an exhaust fan and is also equipped with an opening; towreceive the feed pipe1 22. Located within the drier cylinder or shell ltl'aretwo seriesoff bafile plates or deflectors 25fithos'e ofone series-being locatedfonya; side diametrically opposite to those of the other 1 seriesv and; the deflectors 'ofgthe two series are arranged in staggered or alternated relation as isshown clearly'in Fig. 2. These deflectorsor baffles '25 1 are made in; sectionsja nd all exactly' alikezand hence one only will be described in detail. One of theseba-flie 'plate's is show-n on-an enlarged/scale. in 5 and comprises two sideiplates/QG andiQZ,

' a center lplaite e30. and 'twowexpansidn angle I in members 3-5.and 36 which. latter cohnect "the center plate with the side plates byfineans of bolt and slot connectionsto :prdvide and take here shown which are; connected with the care of expansion and contraction in the dc .flector which is incident to the changing temperature within'the drier. 1 This slot and bolt connection of these plates or sections I provides a self-adjusting connection between them which prevents buckling ofthe deflector anddistorting of the drier shell and avoids-all passage of gas between the sec- .tions and also the entanglement of the material therewith. v, y

The side plates 26 -and27 are secured to the shell 10 by means of angle iron riveted to the plates and to the shell by countersunl; rivets so. as to avoid the heads of the rivets wearing o'ff an'dthereby loosening the plates. These connecting angle irons are numbered -28 in Fig. 5'.

Thecenter plate 30 is fastened to the shell 10: angle irons 31 in the same manner are. fastened the side plates. Fixed to the side and center plates and to the shell 10 and; extending at right angles therefrom are.

a plurality of agitating plates 32any desired number ofwhich may be employed fivebei'n-gplates and with the shell by means of angle I irons riveted. thereto,th e heads ofsaid rivets preferably being counter-sunk. The expansion angles 35 and 36 are'secu-rely riveted to the center plate to form -a firm and rig-id connection. between them. The same legs of these-angles are provided wi'th a suitable I number :ofslotted openings 33 and through which pass bolts 33a which connects the anglesfwith the side plates and thus provide for-iexpansion and contraction between the center andside plates.

These deflectors orba 'files 25 per-form the double function of battles or deflectors for end'of the Ecylinder from the furnace pass through the'shell-andcontact first with :one deflector andthn with another which-causes them to bedeflected and carried into direct contact with the material which is passing t r gh ylinder from the higher rear end and which is being changed from one side to 'the'] other incident tothe rotation of the cylinder. The changing of the direction tifth'e gases byithe 'baflies from a straight or direct flow to a direction at right-angles causesthem to bethoroughly mixed wi'th the material "being dried thereby/It is, of

course, understood that th'e longer thep'eriod' of time that the heating gases are held in contact-with the/material "to be dried the more, thoroughly will rice the effect of the gases on the material and which will consequently reduce the amount of fuel consumed in order to produce the same effect. 7

The arrangement of the deflectors causes them to balance the rotating of the drier and not in any way injure the uniformity of the rotation which would otherwise be' produced. As shown in Fig. 6 the deflectors 25 are arranged'in staggered relation around the periphery of the drum or cylinder on its inner face, each succeeding deflector being oflset at 45 from the proceeding bafile or deflector in reference to the circumference of the circle of the cylinder. Eight of the baflles are shown and are numbered 25, 25a, 25 0, 25c, 25d, 25a, 25/, and 25g. It will thus be seen that by so arranging these deflectors they are all set opposite one another for each 45 in a circle which balances andmaintains uniformity ofrotation in addition to multiplying the number of times the heated gases are deflected towards the bottom of the drier shell thereby bringing the gases into contact with the material a number of times and for long periods increasing the drying qualities and efliciency of the drier. It will be obvious that this arrangement of the deflectors completely baflles the passage of the heat currents and prevents them from passing in a straight line through the drum. I

'The deflectoror bafile plates 25 equipped with agitating blades operate first to defleet the heated gases passing at these points and cause the material, which isbeing constantly lifted by the agitating blades, to

mix more thoroughly with the gases and consequently create a more thoroughdrying process and increase the efficiency of the drier considerably. Secondly, the purpose of these elements isto increase the efficiency of the drier by reducing the cross sectional area of the drier to one-half whereby the velocity of the heated gases is considerably increased and therebycarries out the suddenly accumulated moisture which is driven from the'material to bedried by means of the baffle plates or deflector plates and their agitating blades. These two conditions always exist and theircombination greatly -K; improves the efficiency of the drier.

The blades or plates 32 also operate as agitators for the material being dried by lifting the material from the bottom of the drier shell and carrying it to a position of 45 above the horizontal center line. When in this position the material will s'lide'off the plates 32 directly in front' of the deflectors which is the hottest zone, and the material passing-through this zone will be more effec-' tively dried. The material, as it drops from the top to the bottom of the drier, is entirely surrounded by hot gases which produce a thorough drying effect. Owing to the fact that the agitating plates 32 are secured to the drier shell and tothe deflector this opfed'slowly byithe rotation- 0f the cylinder 10 from neend thereof being constantly a i tated by the blades 32 0f the baffles or eflectors and when it reaches the lower end of said cylinder it will be thorou hly dried and cured and will be discharged into the pit 2 from which it may be conducted by ,a

suitable conveyor not shown. a

Without further descrlption 1t is thought that the features and advantages of the invention will be readily apparent to those skilled in the art, and it will, of course, be understood that changes in the form, proportion and minor details of construction maybe resorted to, without departing from 1 the spirit of the invention or its scope as claimed.

I claim: I

1. In a rotary drier, a rotatable cylinder having an inlet and an outlet, a baffle eXtend ing radially from one wall of the cylinder for a portion of the diameter thereof, said baflie being composed of aplurality ofadjustably connected sections to provide for the expansion and contraction and having means to prevent the passageof air between the sections. 1

2. In a rotary drier, a rotatable cylinder open at both ends and having baffles extending radially from opposed walls of the cyl-. 1

inder for a portion of the diameter thereof, said baflles being provided with means toing through the cylinderand means to operate as agitators for the material being treated. Y s

3. In a rotary drier, a rotatable cylinder open at both ends and having baflies extending radially from opposed walls of the cylfacilitate the bafliing of the air current passinder for a portion of the diameter thereof,

said baflles being provided with means to facilitate the baflling of the air current passing through the cylinder and to operateas agitators for the-material being treated, each of said baflles being'composedvof a plurality of adjustably connected sections to provide) for expansion and contraction.

4. In a rotary drier, a. rotatable cylinder v openat both ends and having baflles extending radially from opposed walls of the cylf inder for a portion ofthe diameter thereof, 7

said baffles being provided with means to facilitate the baffling of the air c'urrentpass.

ing through the cylinder and tooperate as agitators for the material being treated, each i of said "baffles being composed of a plurality ofconnected sections, the connectors between 41.30

I the sectionsbeing in the form of -angleirons;

.fixed to-one section and having la bolt and slot f0onnection with an adj aeent section.

6. A rotary drier including. a rotatable, cylinder prbvided 'ond i'tsinner iace wifih v-a; plurality of inwardly extending :bgxffleplates; each of said'pl-wtes being composed of a plurali tgyef adja-ls tably -conne0ted sections with combined baffle and agitator blades; attached tqsaid gseetions andto the cylinder. 7 r I Y GERHAR D MORRIS BECHTEL. 

